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Date: Thu, 22 Jan 2015 01:19:49 +0000
From: Mans Rullgard <mans@...sr.com>
To: Jean-Christophe Plagniol-Villard <plagnioj@...osoft.com>,
Tomi Valkeinen <tomi.valkeinen@...com>,
linux-fbdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH v2] video: fbdev: fix sys_copyarea
The sys_copyarea() function performs the same operation as
cfb_copyarea() but using normal memory access instead of I/O
accessors. Since the introduction of sys_copyarea(), there
have been two fixes to cfb_copyarea():
- 00a9d699 ("framebuffer: fix cfb_copyarea")
- 5b789da8 ("framebuffer: fix screen corruption when copying")
This patch incorporates the fixes into sys_copyarea() as well.
Signed-off-by: Mans Rullgard <mans@...sr.com>
---
Changed in v2:
- Fixed wrong first/last calculation in bitcpy_rev()
---
drivers/video/fbdev/core/syscopyarea.c | 137 ++++++++++++++++-----------------
1 file changed, 65 insertions(+), 72 deletions(-)
diff --git a/drivers/video/fbdev/core/syscopyarea.c b/drivers/video/fbdev/core/syscopyarea.c
index 844a32f..c1eda31 100644
--- a/drivers/video/fbdev/core/syscopyarea.c
+++ b/drivers/video/fbdev/core/syscopyarea.c
@@ -25,8 +25,8 @@
*/
static void
-bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx,
- const unsigned long *src, int src_idx, int bits, unsigned n)
+bitcpy(struct fb_info *p, unsigned long *dst, unsigned dst_idx,
+ const unsigned long *src, unsigned src_idx, int bits, unsigned n)
{
unsigned long first, last;
int const shift = dst_idx-src_idx;
@@ -86,15 +86,15 @@ bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx,
first &= last;
if (shift > 0) {
/* Single source word */
- *dst = comp(*src >> right, *dst, first);
+ *dst = comp(*src << left, *dst, first);
} else if (src_idx+n <= bits) {
/* Single source word */
- *dst = comp(*src << left, *dst, first);
+ *dst = comp(*src >> right, *dst, first);
} else {
/* 2 source words */
d0 = *src++;
d1 = *src;
- *dst = comp(d0 << left | d1 >> right, *dst,
+ *dst = comp(d0 >> right | d1 << left, *dst,
first);
}
} else {
@@ -109,13 +109,14 @@ bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx,
/* Leading bits */
if (shift > 0) {
/* Single source word */
- *dst = comp(d0 >> right, *dst, first);
+ *dst = comp(d0 << left, *dst, first);
dst++;
n -= bits - dst_idx;
} else {
/* 2 source words */
d1 = *src++;
- *dst = comp(d0 << left | *dst >> right, *dst, first);
+ *dst = comp(d0 >> right | d1 << left, *dst,
+ first);
d0 = d1;
dst++;
n -= bits - dst_idx;
@@ -126,36 +127,36 @@ bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx,
n /= bits;
while (n >= 4) {
d1 = *src++;
- *dst++ = d0 << left | d1 >> right;
+ *dst++ = d0 >> right | d1 << left;
d0 = d1;
d1 = *src++;
- *dst++ = d0 << left | d1 >> right;
+ *dst++ = d0 >> right | d1 << left;
d0 = d1;
d1 = *src++;
- *dst++ = d0 << left | d1 >> right;
+ *dst++ = d0 >> right | d1 << left;
d0 = d1;
d1 = *src++;
- *dst++ = d0 << left | d1 >> right;
+ *dst++ = d0 >> right | d1 << left;
d0 = d1;
n -= 4;
}
while (n--) {
d1 = *src++;
- *dst++ = d0 << left | d1 >> right;
+ *dst++ = d0 >> right | d1 << left;
d0 = d1;
}
/* Trailing bits */
- if (last) {
- if (m <= right) {
+ if (m) {
+ if (m <= bits - right) {
/* Single source word */
- *dst = comp(d0 << left, *dst, last);
+ d0 >>= right;
} else {
/* 2 source words */
d1 = *src;
- *dst = comp(d0 << left | d1 >> right,
- *dst, last);
+ d0 = d0 >> right | d1 << left;
}
+ *dst = comp(d0, *dst, last);
}
}
}
@@ -166,40 +167,35 @@ bitcpy(struct fb_info *p, unsigned long *dst, int dst_idx,
*/
static void
-bitcpy_rev(struct fb_info *p, unsigned long *dst, int dst_idx,
- const unsigned long *src, int src_idx, int bits, unsigned n)
+bitcpy_rev(struct fb_info *p, unsigned long *dst, unsigned dst_idx,
+ const unsigned long *src, unsigned src_idx, unsigned bits,
+ unsigned n)
{
unsigned long first, last;
int shift;
- dst += (n-1)/bits;
- src += (n-1)/bits;
- if ((n-1) % bits) {
- dst_idx += (n-1) % bits;
- dst += dst_idx >> (ffs(bits) - 1);
- dst_idx &= bits - 1;
- src_idx += (n-1) % bits;
- src += src_idx >> (ffs(bits) - 1);
- src_idx &= bits - 1;
- }
+ dst += (dst_idx + n - 1) / bits;
+ src += (src_idx + n - 1) / bits;
+ dst_idx = (dst_idx + n - 1) % bits;
+ src_idx = (src_idx + n - 1) % bits;
shift = dst_idx-src_idx;
- first = FB_SHIFT_LOW(p, ~0UL, bits - 1 - dst_idx);
- last = ~(FB_SHIFT_LOW(p, ~0UL, bits - 1 - ((dst_idx-n) % bits)));
+ first = ~FB_SHIFT_HIGH(p, ~0UL, (dst_idx + 1) % bits);
+ last = FB_SHIFT_HIGH(p, ~0UL, (bits + dst_idx + 1 - n) % bits);
if (!shift) {
/* Same alignment for source and dest */
if ((unsigned long)dst_idx+1 >= n) {
/* Single word */
- if (last)
- first &= last;
- *dst = comp(*src, *dst, first);
+ if (first)
+ last &= first;
+ *dst = comp(*src, *dst, last);
} else {
/* Multiple destination words */
/* Leading bits */
- if (first != ~0UL) {
+ if (first) {
*dst = comp(*src, *dst, first);
dst--;
src--;
@@ -222,29 +218,29 @@ bitcpy_rev(struct fb_info *p, unsigned long *dst, int dst_idx,
while (n--)
*dst-- = *src--;
/* Trailing bits */
- if (last)
+ if (last != -1UL)
*dst = comp(*src, *dst, last);
}
} else {
/* Different alignment for source and dest */
- int const left = -shift & (bits-1);
- int const right = shift & (bits-1);
+ int const left = shift & (bits-1);
+ int const right = -shift & (bits-1);
if ((unsigned long)dst_idx+1 >= n) {
/* Single destination word */
- if (last)
- first &= last;
+ if (first)
+ last &= first;
if (shift < 0) {
/* Single source word */
- *dst = comp(*src << left, *dst, first);
+ *dst = comp(*src >> right, *dst, last);
} else if (1+(unsigned long)src_idx >= n) {
/* Single source word */
- *dst = comp(*src >> right, *dst, first);
+ *dst = comp(*src << left, *dst, last);
} else {
/* 2 source words */
- *dst = comp(*src >> right | *(src-1) << left,
- *dst, first);
+ *dst = comp(*src << left | *(src-1) >> right,
+ *dst, last);
}
} else {
/* Multiple destination words */
@@ -261,14 +257,18 @@ bitcpy_rev(struct fb_info *p, unsigned long *dst, int dst_idx,
/* Leading bits */
if (shift < 0) {
/* Single source word */
- *dst = comp(d0 << left, *dst, first);
+ d1 = d0;
+ d0 >>= right;
} else {
/* 2 source words */
d1 = *src--;
- *dst = comp(d0 >> right | d1 << left, *dst,
- first);
- d0 = d1;
+ d0 = d0 << left | d1 >> right;
}
+ if (!first)
+ *dst = d0;
+ else
+ *dst = comp(d0, *dst, first);
+ d0 = d1;
dst--;
n -= dst_idx+1;
@@ -277,36 +277,36 @@ bitcpy_rev(struct fb_info *p, unsigned long *dst, int dst_idx,
n /= bits;
while (n >= 4) {
d1 = *src--;
- *dst-- = d0 >> right | d1 << left;
+ *dst-- = d0 << left | d1 >> right;
d0 = d1;
d1 = *src--;
- *dst-- = d0 >> right | d1 << left;
+ *dst-- = d0 << left | d1 >> right;
d0 = d1;
d1 = *src--;
- *dst-- = d0 >> right | d1 << left;
+ *dst-- = d0 << left | d1 >> right;
d0 = d1;
d1 = *src--;
- *dst-- = d0 >> right | d1 << left;
+ *dst-- = d0 << left | d1 >> right;
d0 = d1;
n -= 4;
}
while (n--) {
d1 = *src--;
- *dst-- = d0 >> right | d1 << left;
+ *dst-- = d0 << left | d1 >> right;
d0 = d1;
}
/* Trailing bits */
- if (last) {
- if (m <= left) {
+ if (m) {
+ if (m <= bits - left) {
/* Single source word */
- *dst = comp(d0 >> right, *dst, last);
+ d0 <<= left;
} else {
/* 2 source words */
d1 = *src;
- *dst = comp(d0 >> right | d1 << left,
- *dst, last);
+ d0 = d0 << left | d1 >> right;
}
+ *dst = comp(d0, *dst, last);
}
}
}
@@ -317,9 +317,9 @@ void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area)
u32 dx = area->dx, dy = area->dy, sx = area->sx, sy = area->sy;
u32 height = area->height, width = area->width;
unsigned long const bits_per_line = p->fix.line_length*8u;
- unsigned long *dst = NULL, *src = NULL;
+ unsigned long *base = NULL;
int bits = BITS_PER_LONG, bytes = bits >> 3;
- int dst_idx = 0, src_idx = 0, rev_copy = 0;
+ unsigned dst_idx = 0, src_idx = 0, rev_copy = 0;
if (p->state != FBINFO_STATE_RUNNING)
return;
@@ -334,8 +334,7 @@ void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area)
/* split the base of the framebuffer into a long-aligned address and
the index of the first bit */
- dst = src = (unsigned long *)((unsigned long)p->screen_base &
- ~(bytes-1));
+ base = (unsigned long *)((unsigned long)p->screen_base & ~(bytes-1));
dst_idx = src_idx = 8*((unsigned long)p->screen_base & (bytes-1));
/* add offset of source and target area */
dst_idx += dy*bits_per_line + dx*p->var.bits_per_pixel;
@@ -348,20 +347,14 @@ void sys_copyarea(struct fb_info *p, const struct fb_copyarea *area)
while (height--) {
dst_idx -= bits_per_line;
src_idx -= bits_per_line;
- dst += dst_idx >> (ffs(bits) - 1);
- dst_idx &= (bytes - 1);
- src += src_idx >> (ffs(bits) - 1);
- src_idx &= (bytes - 1);
- bitcpy_rev(p, dst, dst_idx, src, src_idx, bits,
+ bitcpy_rev(p, base + (dst_idx / bits), dst_idx % bits,
+ base + (src_idx / bits), src_idx % bits, bits,
width*p->var.bits_per_pixel);
}
} else {
while (height--) {
- dst += dst_idx >> (ffs(bits) - 1);
- dst_idx &= (bytes - 1);
- src += src_idx >> (ffs(bits) - 1);
- src_idx &= (bytes - 1);
- bitcpy(p, dst, dst_idx, src, src_idx, bits,
+ bitcpy(p, base + (dst_idx / bits), dst_idx % bits,
+ base + (src_idx / bits), src_idx % bits, bits,
width*p->var.bits_per_pixel);
dst_idx += bits_per_line;
src_idx += bits_per_line;
--
2.0.5
--
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